Cylinder deactivation entrance and exit control

ABSTRACT

Systems, apparatus, and methods are disclosed that include an internal combustion engine having a plurality of cylinders operable by a valve actuation mechanism. Staging of engine operating conditions is disclosed to facilitate exit from and/or entrance into a cylinder deactivation event.

FIELD OF INVENTION

This invention relates to an internal combustion engine includingmultiple cylinders, and more particularly to controlling entrance and/orexit operating conditions associated with a cylinder deactivation eventof one or more of the multiple cylinders.

BACKGROUND

The cylinders in an internal combustion engine can be disabled in orderto reduce fuel consumption. This may be accomplished by cutting off thesupply of fuel to selected cylinders, particularly to save fuel underlight engine load conditions. This increases the load on the othercylinders and provides some pumping loss reduction, but still requirespumping work to move the air flow through all the cylinders. Anothermethod of cylinder disablement includes disabling or maintaining theintake and exhaust valves of the cylinder in a closed condition, whichfurther reduces pumping work over simply providing a fuel cutoff to thedeactivated cylinders.

Exiting and/or entering a cylinder deactivation event in which theintake and exhaust valves are closed can create operating inefficienciesand lags in responsiveness of the engine. Therefore, furtherimprovements in cylinder deactivation systems and techniques are needed.

SUMMARY

Embodiments include unique systems and methods that include amulti-cylinder internal combustion engine configured to controldeactivation of at least one cylinder of the multiple cylinders. In oneembodiment, the engine includes a valve actuation mechanism connected tothe cylinder(s) and a fuel supply system for supplying fuel to eachcylinder. A controller is configured to receive one or more inputsassociated with one or more operating conditions (such as vehicle speedand/or acceleration) and/or one or more route conditions of the vehicleto control exit from and/or entrance into a cylinder deactivation eventin which the one or more cylinders are deactivated.

This summary is provided to introduce a selection of concepts that arefurther described below in the illustrative embodiments. This summary isnot intended to identify key or essential features of the claimedsubject matter, nor is it intended to be used as an aid in limiting thescope of the claimed subject matter. Further embodiments, forms,objects, features, advantages, aspects, and benefits shall becomeapparent from the following description and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic depiction of a vehicle system including apowertrain.

FIG. 2 is a schematic depiction one embodiment of a part the vehiclesystem of FIG. 1.

FIG. 3 is a schematic cross-section of a deactivation cylinder and valveactuation mechanism.

FIG. 4 is a flow diagram of a procedure for controlling one or moredeactivated cylinders of an internal combustion engine.

FIG. 5 is a flow diagram of another embodiment procedure for controllingone or more deactivated cylinders of an internal combustion engine.

FIG. 6 is a flow diagram of another embodiment procedure for controllingone or more deactivated cylinders of an internal combustion engine.

FIG. 7 is a flow diagram of another embodiment procedure for controllingone or more deactivated cylinders of an internal combustion engine.

DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

For the purposes of promoting an understanding of the principles of theinvention, reference will now be made to the embodiments illustrated inthe drawings and specific language will be used to describe the same. Itwill nevertheless be understood that no limitation of the scope of theinvention is thereby intended, any alterations and further modificationsin the illustrated embodiments, and any further applications of theprinciples of the invention as illustrated therein as would normallyoccur to one skilled in the art to which the invention relates arecontemplated herein.

Referring to FIG. 1, a vehicle system 100 includes an engine 102 fluidlycoupled to an aftertreatment system 104 as shown in FIG. 1. The vehiclesystem 100 further includes a transmission 108 coupled to the engine102, comprising a portion of a powertrain 105 for propelling vehicle 101via wheels 109. The engine 102 may be any type of internal combustionengine, including at least a diesel, gasoline, or natural gas engine,and/or combinations thereof. The aftertreatment system 104 may includeany type of aftertreatment components 106 known in the art, which mayinclude catalytic and/or filtration components. Example aftertreatmentcomponents 106 may include, without limitation, oxidation catalysts(e.g., a diesel oxidation catalyst (“DOC”), NO_(x) treatment components(e.g., three-way catalyst, lean NOx catalyst, selective catalyticreduction (“SCR”) catalyst, etc.), a filtration component (eithercatalyzed or uncatalyzed, e.g., a diesel particulate filter (“DPF”), anda cleanup catalyst (e.g., an ammonia oxidation catalyst).

In certain embodiments, the engine 102 includes a lean combustion enginesuch as a lean burn gasoline engine, or a diesel cycle engine. Incertain embodiments, the engine 102 may be any engine type producingemissions that may include an exhaust gas recirculation (EGR) system,for example to reduce NO_(x) emissions from the engine 102. In theillustrated embodiment of FIG. 2, the vehicle system 100 includes anengine 102 having an in-line 4 cylinder arrangement for illustrationpurposes. However, V-shaped arrangements and other any number ofcylinders with V-shaped and with in-line arrangements are alsocontemplated.

The engine 102 includes a number of cylinders 103 a, 103 b (collectivelyreferred to as cylinders 103.) The engine 102 includes nominal cylinders103 a which are operated with a nominal valve lift profile under bothnominal operating events and cylinder deactivation events, and one ormore deactivation cylinders 103 b which are operated with a deactivatedlift profile in response to a cylinder deactivation event being present.The deactivation cylinders 103 b can be operated with the nominal valvelift profile when cylinder deactivation event conditions are notpresent. In the illustrated embodiment of FIG. 2, two cylinders ofengine 102 are deactivation cylinders 103 b, but more or fewer than twocylinders can be deactivation cylinders, including all cylinders 103. Inaddition, the cylinders identified as nominal cylinders 103 a anddeactivation cylinders 103 b in FIG. 2 can be in any order. Furthermore,any known type of mechanism for deactivating one or more cylinders 103is contemplated.

A typical multi-cylinder engine 102 has an engine block 200 withmultiple cylinders 103, and, as shown in FIG. 3, a piston 202 in eachcylinder that is operably attached to a crankshaft 204. There is also atleast one intake valve 206 and at least one exhaust valve 208 that allowpassage of air into and out of each cylinder 103. A combustion chamber210 is formed inside each cylinder. The typical engine 102 operates on afour-stroke cycle that sequentially includes an air intake stroke, acompression stroke, a power stroke, and an exhaust stroke. As usedherein, one cycle of the cylinder or engine occurs at the completion ofthese four strokes.

When cylinders are deactivated, the valve opening devices of the valveactuation mechanism 220 can be collapsed so the intake and exhaustvalves of the deactivated cylinder(s) 103 b remain in a completelyclosed condition during a cylinder deactivation event. In addition, fueldelivery to the deactivated cylinder(s) 103 b is stopped. The activecylinders 103 a can then be operated with a greater amount of air andfuel to meet the engine power demands. The active cylinders 103 a thusoperate with a greater air flow, reducing pumping losses, and improvedfuel efficiency. However, the transition from a nominal lift profile fordeactivation cylinders 103 b into a deactivated lift profile for thecylinder deactivation event, and the transition from a cylinderdeactivation event lift profile to a nominal lift profile for thedeactivation cylinders 103 b, can result in inefficiencies and reducedresponsiveness of engine 102.

The present vehicle system 100 includes a valve actuation mechanism 220that is configured and/or controlled to improve performance at thetransitions out of and into and cylinder deactivation event valve liftprofile for deactivation cylinders 103 b. For example, in oneembodiment, valve actuation mechanism 220 provides a first non-zero liftprofile for opening and closing intake valve 206 of each cylinder 103 inresponse to nominal engine operating conditions. The exhaust valve(s) ofeach cylinder can also be opened and closed with a non-zero valve liftprofile that is the same or different from that of the non-zero-valvelift profile that opens and closes the intake valves 206. Valveactuation mechanism 220 is further configured to be switched to adeactivated valve lift profile for operation of intake valves 206 and/orexhaust valves 208 of deactivation cylinders 103 b in response to acylinder deactivation event where cylinders 103 b are deactivated.

The entrance into or exit from a cylinder deactivation event can bedetermined in response to one or more engine and/or vehicle operatingconditions, such as a low engine load and/or low engine speed in oneembodiment. In another embodiment, an increase in speed or accelerationof the vehicle determines whether to exit or enter a cylinderdeactivation event, such as when the vehicle is motoring or coasting.The term “motoring” or “motored”, as used hereinafter, describes anoperating condition in which the engine 102 is not presently injectingfuel, and has zero torque requirement, but is turning because the engine102 is connected to the transmission 108, which is turning due torotation of the wheels 109 connected thereto.

In one embodiment, valve actuation mechanism 220 includes hardwaremounted in a head 212 of engine 102 and control algorithms that areinternal to the controller 140. The cylinder deactivation hardwareincludes a valve opening mechanism 214, 216 for respective ones ofintake and exhaust valves 206, 208 of each cylinder 103. The valveactuation mechanism 220 also comprises a hydraulic subsystem (not shown)that supplies pressurized oil from an engine oil pump (not shown) toeach valve opening mechanism 214, 216. In one embodiment, the valveopening mechanism 214, 216 is comprised of a lifter and a locking pinmechanism that is inserted between the camshaft 222, 224 and therespective valves 206, 208.

A typical valve train is comprised of the camshafts 222, 224, or inanother embodiment a single cam shaft. The plurality of valves 206, 208are normally closed to a zero lift position against their respectivevalve seats and are spring-mounted in the head 212. The valve train isoperable to open the plurality of exhaust valves 208, the plurality ofintake valves 206, or both, depending upon the engine design. Eachcamshaft 222, 224 is a long rod that is mounted in the engine 102 androtates around its longitudinal axis. Each camshaft 222, 224 has camlobes 226, 228, respectively, that correspond to and operate each valve206, 208. Cam lobes 226, 228 are typically cut into the respectivecamshaft 222, 224 such that they are eccentric to the axis of rotationof the respective camshaft 222, 224.

Each lobe 226, 228 has an eccentric portion and a portion that isconcentric to the longitudinal axis of the cam shaft. The concentricportion is defined by and can be referred to as the cam base circle, andthe eccentric portion projects from the base circle to define anon-zero-lift profile to open and close the respective valve 206, 208for a specified lift and duration from its valve seat. For example, theintake valve cam lobe 226 can define a non-zero lift profile 300 asshown in FIG. 3. Each lobe 226, 228 is in physical contact with arespective one of the valve opening mechanisms 214, 216, which are eachcomprised of a lifter and a locking pin mechanism. The valve openingmechanisms 214, 216 are in physical contact with a respective one of thevalves 206, 208. The rotation of the camshaft 222, 224 causes respectivevalve 206, 208 to open according to the non-zero lift profile defined bythe corresponding lobe 226, 228 when the position of the respectivecamshaft 222, 224 is such that the eccentric portion of itscorresponding lobe 226, 228 is in contact with the adjacent valveopening mechanism 214, 216.

For deactivation cylinders 103 b, such as shown in FIG. 2, the valveactuation mechanism 220 is operable to substantially or completelydisable each intake valve 206, substantially or completely disable eachexhaust valve 208, and substantially or completely disable each fuelinjector 162 for each cylinder 103 b that is to be deactivated inresponse to a cylinder deactivation condition. In one embodiment, thevalve actuation mechanism 220 disables half of the cylinders 103 when inthe deactivation mode. In a specific embodiment, camshaft 222 isswitchable to place a second cam lobe 226′ to operate the intake valves206 of each of the deactivation cylinders 103 b with a deactivated liftprofile defined by second cam lobe 226′ for intake valve 206 of thedeactivation cylinder(s) 103 b during cylinder deactivation conditions.Camshaft 224 associated with the exhaust valves 208 is also switchablefrom a third non-zero lift profile defined by a third cam lobe 228 to afourth profile at a fourth cam lobe 228′ that defines a deactivated liftprofile that maintains the respective exhaust valve 208 at eachdeactivation cylinder 103 b in a closed position. The deactivated liftprofiles of cam lobes 226′, 228′ can be zero lift profiles so that therespective valve(s) remains in a closed position against its valve seatin response to cylinder deactivation events. Other embodimentscontemplate lift profiles that are non-zero but effectively providecylinder deactivation. In still other embodiments, any suitable valveactuation mechanism 220 for deactivating one or more cylinders 103 iscontemplated, and it should be understood the present disclosure is notlimited to the specifically disclosed embodiment unless noted otherwise.

Referring back to FIG. 2, in the vehicle system 100 exhaust flow 134produced by cylinders 103 is provided to an exhaust manifold 130 andoutlet to an exhaust passage 132. Vehicle system 100 may include anexhaust gas recirculation (EGR) passage 111 to provide an EGR flow 113that combines with an intake flow 118 at a position upstream of anintake manifold 115. Intake manifold 115 provides a charge flowincluding the intake flow 118 and, if provided, with EGR flow 108 tocylinders 103. Intake manifold 115 is connected to an intake passage 117that includes an intake throttle 107 to regulate the charge flow tocylinders 103. Intake passage 117 may also include a charge air cooler(not shown) to cool the charge flow provided to intake manifold 115.Intake passage 117 may also include an optional compressor 170 tocompress the intake air flow received from an intake air cleaner (notshown.)

The EGR flow 113 may combine with the intake flow 118 at an outlet ofEGR passage 111, at a mixer, or by any other arrangement. In certainembodiments, the EGR flow 113 returns to the intake manifold 115directly. In the illustrated embodiment, EGR flow 113 mixes with theintake flow 118 downstream of throttle 107 so that exhaust pressure oncylinders 103 is closely aligned with intake pressure, which reducespumping losses through cylinders 103. In other embodiments, EGR passage111 can include an EGR cooler (not shown) and a bypass (not shown) witha valve that selectively allows EGR flow to bypass the EGR cooler. Thepresence of an EGR cooler and/or an EGR cooler bypass is optional andnon-limiting.

Cylinders 103 are connected to an exhaust system that includes anexhaust manifold 130 that receives exhaust gases in the form of exhaustflow 134 from cylinders 103 and an exhaust passage 132 that receivesexhaust gas from exhaust manifold 130. In other embodiments, aturbocharger 171 includes a turbine 172 in exhaust passage 132 isprovided that is operable via the exhaust gases to drive a compressor174 in intake passage 117. Turbine 172 may include a bypass (not shown)or a size-controllable inlet such as is provided with a variablegeometry turbine (VGT) to control the exhaust flow therethrough and thusthe speed of turbine 172. Exhaust passage 132 includes one or moreaftertreatment components 106 in exhaust passage 132 configured to treatemissions in the exhaust gas. Other embodiments contemplate an exhaustthrottle (not shown) in the exhaust passage 132.

Vehicle system 100 further includes a fuel system 150 that is operableto provide fuel from a fuel storage source 152, such as a fuel tank, tocylinders 103. In the illustrated embodiment, the fuel storage source152 includes, for example, an onboard fuel pump 154 which delivers fuelfrom the source 152 via a conduit 156 through a filter (not shown) to acommon supply rail 158. The common rail 158 feeds fuel via respectivefuel lines 160 to a plurality of fuel injectors 162, at least one percylinder, and in this example, four injectors 162. The common rail 158can also be connected via conduit 156 to a pressure regulator valve 164which in turn is connected to conduit 166 to vent fuel vapor to theintake passage 117 when the pressure in the rail 158 exceeds apredetermined maximum pressure. The fuel pump 154 is operated through arelay or other suitable connection to controller 140. It should beunderstood, however, that any suitable fuel system is contemplated.

A direct injector, as utilized herein, includes any fuel injectiondevice that injects fuel directly into the cylinder volume, and iscapable of delivering fuel into the cylinder volume when the intakevalve(s) and exhaust valve(s) are closed. The direct injector 162 may bestructured to inject fuel at the top of the cylinder 103. In certainembodiments, the direct injector 162 may be structured to inject fuelinto a combustion pre-chamber. Each cylinder 103 may include one or moredirect injectors 162. The direct injectors 162 may be the primary or theonly fueling device for the cylinders 103, or alternatively the directinjectors may be an auxiliary or secondary fueling device for thecylinders 103. In certain embodiments, the direct injectors 162 arecapable of providing the entire designed fueling amount for thecylinders 103 at any operating condition. Alternatively, the directinjectors 162 may be only partially capable, for example the directinjectors 162 may be capable of providing a designated amount of fuelfor a specific purpose.

In still other embodiments, cylinders 103 include a port injector (notshown) in addition to or alternatively to direct injectors 162. In theseembodiments, the intake manifold 115 may be divided, or the port fuelinjectors may be positioned such that no other cylinder 103 in thevehicle system 100 is downstream of the port fuel injector, i.e. onlythe target cylinder is downstream of the respective port fuel injector.

The fuel supply to the combustion chamber of each cylinder is controlledby a fuel control module 142 that is a separate controller or a part ofcontroller 140. Fuel control module 142 operates the injectors 162according to a fuel command produced by controller 140 in response toengine operating conditions. The controller 140 is connected to the fuelpump 154 and to a plurality of other sensors shown schematically assensor 170. The sensors 170 may include, but are not limited to, sensorswhich monitor or measure vehicle speed, vehicle acceleration, engineposition, engine speed, manifold static pressure, mass air flow into themanifold, engine temperature, air temperature, cam shaft position (inletand exhaust), inlet manifold tuning valves, barometric pressure, EGRamount, VGT position, torque demand, gear position, etc. In addition,controller 140 may be configured to receive from, for example, one ormore sensors 170 or from a memory 143 of controller 140, a proximity orposition of other vehicles, a spacing or distance to one or more othervehicles, a speed of one or more other vehicles, route conditions,upcoming grade conditions, GPS data, mapping data, inputs from one ormore other vehicles or a forward looking radar system, and/or one ormore models of vehicle system 100 including estimated mass, aerodynamicdrag, and other conditions associated with vehicle 101.

In certain embodiments, the vehicle system 100 includes a controller 140structured to perform certain operations to control operations of engine102. In certain embodiments, the controller 140 forms a portion of aprocessing subsystem including one or more computing devices havingmemory, processing, and communication hardware. The controller 140 maybe a single device or a distributed device, and the functions of thecontroller 140 may be performed by hardware or software. The controller140 may be included within, partially included within, or completelyseparated from an engine controller (not shown). The controller 140 isin communication with any sensor or actuator throughout the vehiclesystem 100, including through direct communication, communication over adatalink, and/or through communication with other controllers orportions of the processing subsystem that provide sensor and/or actuatorinformation to the controller 140.

In certain embodiments, the controller 140 is described as functionallyexecuting certain operations. The descriptions herein including thecontroller operations emphasizes the structural independence of thecontroller, and illustrates one grouping of operations andresponsibilities of the controller. Other groupings that execute similaroverall operations are understood within the scope of the presentapplication. Aspects of the controller may be implemented in hardwareand/or by a computer executing instructions stored in non-transientmemory on one or more computer readable media, and the controller may bedistributed across various hardware or computer based components.

Example and non-limiting controller implementation elements includesensors providing any value determined herein, sensors providing anyvalue that is a precursor to a value determined herein, datalink and/ornetwork hardware including communication chips, oscillating crystals,communication links, cables, twisted pair wiring, coaxial wiring,shielded wiring, transmitters, receivers, and/or transceivers, logiccircuits, hard-wired logic circuits, reconfigurable logic circuits in aparticular non-transient state configured according to the modulespecification, any actuator including at least an electrical, hydraulic,or pneumatic actuator, a solenoid, an op-amp, analog control elements(springs, filters, integrators, adders, dividers, gain elements), and/ordigital control elements.

The listing herein of specific implementation elements is not limiting,and any implementation element for any controller described herein thatwould be understood by one of skill in the art is contemplated herein.The controllers herein, once the operations are described, are capableof numerous hardware and/or computer based implementations, many of thespecific implementations of which involve mechanical steps for one ofskill in the art having the benefit of the disclosures herein and theunderstanding of the operations of the controllers provided by thepresent disclosure.

Certain operations described herein include operations to interpret ordetermine one or more parameters. Interpreting or determining, asutilized herein, includes receiving values by any method known in theart, including at least receiving values from a datalink or networkcommunication, receiving an electronic signal (e.g. a voltage,frequency, current, or PWM signal) indicative of the value, receiving asoftware parameter indicative of the value, reading the value from amemory location on a non-transient computer readable storage medium,receiving the value as a run-time parameter by any means known in theart, and/or by receiving a value by which the interpreted parameter canbe calculated, and/or by referencing a default value that is interpretedto be the parameter value.

Certain systems are described following, and include examples ofcontroller operations in various contexts of the present disclosure. Incertain embodiments, the controller 140 interprets a cylinderdeactivation event in response to one or more vehicle operating and/orroute conditions, and in response to entering the cylinder deactivationevent the controller 140 provides a cylinder deactivation command thatcuts fueling to one or more of deactivation cylinders 103 b and thenswitches operation of their respective intake valves 206 and exhaustvalves 208 to second cam lobe 226′ and fourth cam lobe 228′,respectively, each having a cylinder deactivation lift profile asdiscussed above. In certain other embodiments, the controller 140interprets a cylinder deactivation event in response to one or morevehicle operating and/or route conditions, and in response to exitingthe cylinder deactivation event the controller 140 provides a cylinderactivation command that first switches operation of their respectiveintake valves 206 and exhaust valves 208 to first cam lobe 226 and thirdcam lobe 228 to open and close the intake and exhaust valves, and thenprovides fueling to the re-activated cylinders. In certain otherembodiment, the speed of the turbocharger 171 is increased prior tofueling the re-activated cylinders.

The determination that conditions for entering and exiting a cylinderdeactivation event includes determining or interpreting one or morevehicle operating conditions understood in the art indicating thatcylinder deactivation produces favorable operating conditions, such asat low engine load conditions where the remaining non-deactivatedcylinders 103 a can satisfy the engine load requirements and fuelefficiency can be achieved by cutting fueling to one or more of thedeactivation cylinders 103 b. However, other conditions in which thecylinder deactivation event is present are also contemplated.

In certain other embodiments, the controller 140 interprets a motoredmode along with a cylinder deactivation event in response to one or morevehicle operating conditions. In response to the motored mode beinginitiated fuel is cut-off to all cylinders 103 and in response to thecylinder deactivation event the controller 140 provides a cylinderdeactivation command that switches operation of one or more deactivationcylinders 103 b and their respective intake valves 206 and exhaustvalves 208 to second cam lobe 226′ and fourth cam lobe 228′ each havinga cylinder deactivation lift profile. The determination that conditionsfor entering and/or exiting a motored mode exist includes determining orinterpreting one or more vehicle operating conditions understood in theart indicating that motoring produces favorable operating conditions,such as coasting in response to certain terrain and grade conditionswhere no fueling is needed to propel the vehicle. Deactivation of one ormore of the cylinders 103 during the motored mode can produce furtherfavorable operating conditions, such as temperature control of theaftertreatment system 104 during the motored mode by controlling theamount of air flow through engine 102.

The operation of the engine 102 is controlled by the controller 140 inresponse to vehicle operating conditions sensed by the sensorsrepresented by sensor(s) 170. Controller 140 is connected to the fuelinjectors 162, either indirectly as shown through fuel control module142, or directly, to control the injector operation. The controller 140can determine the injection timing and the injection period or pulsewidth. Under normal or nominal engine operating conditions, fuel isprovided to all cylinders 103. Under a cylinder deactivation event, fuelin only provided to cylinders 103 a and cut off from deactivationcylinders 103 b. Under a motored mode, fueling is cut-off to allcylinders 103.

The fuel injectors 162 may inject the fuel supply directly into eachrespective cylinder 103 or may supply fuel to the inlet valve ports, theinjection timing being controlled the controller 140. During a cylinderdeactivation event the supply of fuel to the deactivation cylinders 103b is cut off by individually disabling the respective fuel injectors 162with the disablement being controlled by the controller 140 with afueling command which disables the fuel injection to one or more of thedeactivation cylinders 103 b while the nominal cylinders 103 b firenormally, or are compensated with additional fuel and air flow to meetpower demands. During a motored mode of operation the supply of fuel toall cylinders 103 is cut off by individually disabling the respectivefuel injectors 162 with the disablement being controlled by thecontroller 140 with a fueling command.

Referring to FIG. 4, there is shown a flow diagram of a procedure 400for exiting a cylinder deactivation (CDA) event of or more of thecylinders 103 of engine 102 in response to a speed of the vehicle 101.Procedure 400 begins at operation 402 in which it is determined whethera CDA event is active. If conditional 402 is negative procedure 400continues at operation 404 to operate engine 102 without CDA. Ifconditional 402 is positive, procedure 400 continues at operation 406 tomonitor for or determine the presence of one or more CDA event exitconditions.

Procedure 400 continues at conditional 408 to determine if the vehiclespeed (Vsp) is less than a re-engagement threshold to stage the exitfrom the CDA event. If conditional 408 is negative, procedure 400returns to operation 406 to monitor for CDA event exit condition(s). Ifconditional 408 is positive, procedure 400 continues at operation 410 tostage the exit from the CDA event by first engaging the valve train toactivate the deactivated intake and exhaust valves 206, 208 and/or byengaging the turbocharger 171 of vehicle system 100. Engagingturbocharger 171 can include, for example, controlling a bypass and/oran inlet of turbine 172 to increase the turbocharger speed from acurrent turbocharger speed.

Procedure 400 continues from operation 410 at conditional 412 todetermine if the Vsp is less than a fueling threshold. If conditional412 is negative, procedure 400 continues at operation 416 to operate thevalve train and/or turbocharger without fueling the one or morecylinders that were deactivated during the CDA event. The vehicle speedis further monitored to determine when Vsp is less than the fuelingthreshold. If conditional 412 is positive, procedure 400 continues atoperation 414 to fuel the cylinder(s) that were deactivated during theCDA event, and the engine is operated without a CDA event being present.The staging of the re-engagement of the valve train and/or turbochargerprovides a more efficient and responsive transition to non-CDAoperations at operation 404.

Referring to FIG. 5, there is shown another embodiment procedure 500.Procedure 500 involves exiting a CDA event of one or more of thecylinders 103 of engine 102 in response to one or more route conditionsof vehicle 101. Procedure 500 begins at conditional 502 in which it isdetermined whether a CDA event is active. If conditional 502 is negativeprocedure 500 continues at operation 504 to operate engine 102 withoutCDA being active. If conditional 502 is positive, procedure 500continues at operation 506 to monitor for or determine one or more CDAevent exit conditions.

Procedure 500 continues at conditional 508 to determine if one or moreroute conditions indicate that a fueling event for the deactivatedcylinder(s) is needed. The route conditions can include, for example,look-ahead grade profile data such as from a stored map and GPS datathat can be employed with a vehicle model to predict a timing for thefueling requirement to be initiated. Another example route conditionincludes radar data from a radar 175 (FIG. 1) indicating a spacing ordistance between the vehicle and a second, target vehicle 177. Stillother route conditions include data, such as from vehicle-to-vehiclecommunications, indicating positioning and/or speed or adjacent vehicles177 relative to vehicle 101 to project the need to initiate fueling. Ifconditional 508 is negative, procedure 500 returns to operation 506 tocontinue to monitor for or determine CDA event exit condition(s).

If conditional 508 is positive, procedure 500 continues at operation 510to stage the exit from the CDA event by engaging the valve train toactivate the deactivated intake and exhaust valves 206, 208 of thedeactivated cylinder(s) and/or by engaging the turbine 172 ofturbocharger 171 of vehicle system 100 to increase its speed beforefueling. Procedure 500 continues at operation 512 after engaging thevalve train and/or turbocharger to fuel the deactivated cylinders toexit the CDA event. The staging of the re-engagement of the valve trainand/or turbocharger provides a more efficient and responsive transitionto non-motored and non-CDA engine operations at operation 504.

Referring to FIG. 6, there is shown a flow diagram of a procedure 600for exiting a motored mode of operation during the CDA event in whichfueling of all cylinders 103 is cut off and the valve train of one ormore deactivation cylinders 103 b is disengaged. The procedure 600 exitsthe motored CDA event in response to a speed and/or acceleration of thevehicle 101. Procedure 600 begins at operation 602 in which it isdetermined whether a motored CDA event is active. If conditional 602 isnegative procedure 600 continues at operation 604 to operate engine 102without a motored CDA event. If conditional 602 is positive, procedure600 continues at operation 606 to monitor for one or more motored CDAevent exit conditions.

Procedure 600 continues at conditional 608 to determine if the Vspand/or vehicle acceleration (Vacc) is less than a re-engagementthreshold. If conditional 608 is negative, procedure 600 returns tooperation 606 to monitor for motored CDA event exit condition(s). Ifconditional 608 is positive, procedure 600 continues at operation 610 tostage the exit from the motored CDA event by engaging the valve train toactivate the deactivated intake and exhaust valves 206, 208 of thedeactivated cylinders 103 b and/or by engaging the turbine 172 ofturbocharger 171 of vehicle system 100 to increase turbocharger speed,as discussed above.

Procedure 600 continues at conditional 612 to determine if Vsp and/orVacc is less than a fueling threshold. If conditional 612 is negative,procedure 600 continues at operation 616 to operate the valve trainand/or turbocharger without fueling the cylinders 103 b that weredeactivated during the motored CDA event. Vsp and Vacc is furthermonitored at operation 610 to determine if Vsp and/or Vacc is less thanthe fueling threshold. If conditional 612 is positive, procedure 600continues at operation 614 to fuel all the cylinders 103 that were cutoff from fueling during the motored CDA event. The staging of there-engagement of the valve train and/or turbocharger before establishingfueling provides a more efficient and responsive transition tonon-motored CDA operations at operation 604.

Referring to FIG. 7, there is shown another embodiment procedure 700.Procedure 700 involves entering and exiting a motored CDA event of ormore of the cylinders 103 of engine 102 in response to one or more routeconditions of vehicle 101. Procedure 700 begins at conditional 702 inwhich it is determined whether a motored CDA event is active. Ifconditional 702 is negative, procedure 700 continues at operation 704 tooperate engine 102 without CDA. If conditional 702 is positive,procedure 700 continues at operation 706 to monitor for one or moremotored CDA event exit conditions.

Procedure 700 continues from operation 706 at conditional 708 todetermine if one or more route conditions indicate that a fueling eventor requirement for the deactivated cylinders is needed. For example, theroute conditions can include, for example, look-ahead grade profile datasuch as from a stored map and GPS data that can be employed with avehicle model stored in controller 140 to predict a timing of thefueling requirement. Another example of route conditions include radardata indicating a spacing or distance between the vehicle 101 and asecond, target vehicle 177. Still other route conditions include data,such as from vehicle-to-vehicle communications, indicating positioningand/or speed of adjacent vehicles relative to vehicle 101 to project theneed and timing to initiate fueling. For example, in one embodiment, thefueling requirement timing is determined based on the proximity/speed ofother vehicles and the speed, estimated mass, aerodynamic drag, andupcoming grade of vehicle 101.

If conditional 708 is negative, procedure 700 returns to operation 706to monitor for motored CDA event exit condition(s). If conditional 708is positive, procedure 700 continues at operation 710 to stage the exitfrom the motored CDA event by engaging the valve train to activate thedeactivated intake and exhaust valves 206, 208 and/or by engaging theturbocharger 171 of vehicle system 100. Procedure 700 continues atoperation 712 after engaging the valve train and/or turbocharger to fuelall cylinders 103 to exit the motored CDA event. The staging of there-engagement of the valve train and/or turbine provides a moreefficient and responsive transition to non-motored and non-CDAoperations at operation 704.

Procedure 700 further includes an operation 714 that continues fromoperation 704 to monitor vehicle 101 for motored CDA event entranceconditions. Conditional 716 evaluates route conditions to determinewhether a de-fueling or fuel cut off event for all cylinders 103 isindicated. If conditional 716 is negative, procedure 700 returns tooperation 714 to monitor for motored CDA event entrance conditions. Ifconditional 716 is positive, procedure 700 continues at operation 718 tostage the entrance to the motored CDA event by de-fueling the cylinders103. After the fuel is cut-off, one or more cylinders 103 aredeactivated after the fuel is cut off from the cylinders 103 bydisengaging the valve train for the deactivated cylinders 103 b.

Various aspects of the present disclosure are contemplated. {Insertclaims here after approval}

While the invention has been illustrated and described in detail in thedrawings and foregoing description, the same is to be considered asillustrative and not restrictive in character, it being understood thatonly certain exemplary embodiments have been shown and described. Thoseskilled in the art will appreciate that many modifications are possiblein the example embodiments without materially departing from thisinvention. Accordingly, all such modifications are intended to beincluded within the scope of this disclosure as defined in the followingclaims.

In reading the claims, it is intended that when words such as “a,” “an,”“at least one,” or “at least one portion” are used there is no intentionto limit the claim to only one item unless specifically stated to thecontrary in the claim. When the language “at least a portion” and/or “aportion” is used the item can include a portion and/or the entire itemunless specifically stated to the contrary.

What is claimed is:
 1. A system comprising: an internal combustionengine for propelling a vehicle, the internal combustion engineincluding a plurality of cylinders, each of the cylinders including atleast one intake valve and at least one exhaust valve; a valve actuationmechanism connected to each of the plurality of cylinders, the valveactuation mechanism including a lifting mechanism for opening andclosing the at least one intake valve and the at least one exhaustvalve; a fueling system connected to each of the plurality of cylindersfor providing fuel to the plurality of cylinders; a controller operablyconnected with the valve actuation mechanism and the fueling system,wherein the controller is configured to: determine an active cylinderdeactivation event associated with the at least one cylinder in whichthe valve actuation mechanism is deactivated and the fueling is cut offfrom the at least one cylinder; in response to the active cylinderdeactivation event being present, determine at least one of a speed ofthe vehicle and an acceleration of the vehicle; and in response to theat least one of the speed and the acceleration crossing a firstthreshold, activating the valve actuation mechanism to open and closethe at least one intake valve and the at least one exhaust valve of theat least one cylinder, and in response to the at least one of the speedand the acceleration crossing a second threshold after crossing thefirst threshold, fueling the at least one cylinder with the fuelingsystem.
 2. The system of claim 1, wherein, before fueling the at leastone cylinder, the controller is further configured to increase a speedof a turbocharger connected to the internal combustion engine inresponse to the at least one of the speed and the acceleration crossingthe first threshold.
 3. The system of claim 1, wherein the cylinderdeactivation event includes remaining ones of the plurality of cylindersreceiving fueling and the valve actuation mechanism opening and closingthe at least one intake and exhaust valves of the remaining ones of theplurality of cylinders.
 4. The system of claim 3, wherein the controlleris configured to determine the speed of the vehicle and the firstthreshold is greater than the second threshold.
 5. The system of claim1, wherein the cylinder deactivation event includes a motored mode ofoperation of the internal combustion engine in which fueling is cut offto all the plurality of cylinders and a portion of the plurality ofcylinders have the valve actuation mechanism deactivated.
 6. The systemof claim 5, wherein the first threshold is less than the secondthreshold.
 7. A method for operating a vehicle, comprising: determininga cylinder deactivation event associated with at least one cylinder ofan internal combustion engine is present during which a valve actuationmechanism operably connected to the at least one cylinder is deactivatedand fueling to the at least one cylinder is cut off; in response to thecylinder deactivation event being present, determining at least one of aspeed of the vehicle and an acceleration of the vehicle; in response tothe at least one of the speed and acceleration crossing a firstthreshold, activating the valve actuation mechanism to open and close atleast one intake valve and at least one exhaust valve of the at leastone cylinder; and in response to the at least one of the speed andacceleration crossing a second threshold after crossing the firstthreshold, fueling the at least one cylinder.
 8. The method of claim 7,further comprising increasing a speed of a turbocharger in the exhaustsystem in response to the at least one of the speed and accelerationcrossing the first threshold and before the at least one of the speedand the acceleration crosses the second threshold.
 9. The method ofclaim 7, wherein the cylinder deactivation event includes remaining onesof the plurality of cylinders receiving fueling and the valve actuationmechanism opening and closing the at least one intake and exhaust valvesof the remaining ones of the plurality of cylinders, and furthercomprising determining the speed of the vehicle and the first thresholdis greater than the second threshold.
 10. The method of claim 7, whereinthe internal combustion engine operates in a motored mode of operationduring the cylinder deactivation event and the first threshold is lessthan the second threshold, wherein fueling is cut off to all cylindersof the internal combustion engine in the motored mode.
 11. The method ofclaim 10, wherein the internal combustion engine includes a plurality ofcylinders and in the motored mode of operation a remaining portion ofthe plurality of cylinders include intake and exhaust valves that areopened and closed by the valve actuation mechanism.